Does hardening of the arteries begin in the gut?

Natural Health News — New research links the diversity of the ‘good bacteria’ in our guts to a key feature of cardiovascular disease – hardening of the arteries.

Hardening of the arteries happens at different rates in different people as we age. It is known to be a factor in cardiovascular risk but there are no straightforward answers to what causes the arteries to harden in the first place.

A number of diseases – and, in particular, inflammation-related conditions – are linked to low microbiome diversity. While a link with gut diseases, such as the inflammatory bowel disease may seem obvious, low microbiome diversity has also been found to be connected to conditions such as arthritis, psoriasis, asthma, eczema and allergies.

Type-2 diabetes, obesity and weight gain – which are also linked to inflammation – also appear to be linked to a lower numbers of gut bugs. Because these conditions are known risk factors for heart disease the research team wanted to determine whether low microbiome diversity was directly linked to poor heart health, or if it instead was linked to type-2 diabetes, obesity and weight, which, in turn, are tied to poor heart health.

Quick summary

» New research has linked a low diversity of gut bacteria, which can be linked to systemic inflammation, to hardening of the arteries in women.

» Even after adjusting for all other risk factors, women whose microbiome lacked diversity were significantly more likely to suffer from this condition – which is a factor in heart disease.

» The findings suggest that a diet with higher levels of healthy fibre and/or supplementation with a range of probiotics would be a useful preventative strategy.

Diversity is the key

The researchers took measurements of arterial stiffening alongside data on the composition of the gut microbiomes in 617 middle-aged female twins.

Results showed that arterial stiffness was significantly higher in women with lower diversity of healthy bacteria in the gut. The scientists were also able to identify specific microbes which were linked to a lower risk of arterial stiffening; including species from Ruminococcaceae, Rikenellaceae,Clostridiaceae, and Barnesiellaceae families. These microbes have also previously been associated with a lower risk of obesity.

Lead author Dr Ana Valdes, from the University of Nottingham’s School of Medicine and NIHR Nottingham Biomedical Research Centre, said: “We know that a substantial proportion of serious cardiovascular events like heart attacks are not explained by traditional risk factors such as obesity and smoking, particularly in younger people and in women and that arterial stiffness is related to risk in those groups. So our results reveal the first observation in humans linking the gut microbes and their products to lower arterial stiffness.”

Diet as prevention

The issue of heart health and disease has been shown, by recent research to be much more nuanced than traditional advice to eat less fat and/or cholesterol. Indeed, getting enough healthy fats can actually help improve microbiome diversity.

Co-author Dr Cristina Menni, from the Department of Twin Research and Genetic Epidemiology at King’s College London, suggests that dietary approaches could be a useful first line for prevention. “There is considerable interest in finding ways to increase the diversity of gut microbes for other conditions such as obesity and diabetes. Our findings now suggest that finding dietary interventions to improve the healthy bacteria in the gut could also be used to reduce the risk of heart disease.”

The research, published in the European Heart Journal, concludes that cardiovascular risk that is not explained by the usual risk factors could, in the future, be enhanced by paying attention to the health of the gut microbiome. Their results, also suggest that targeting the microbiome through diet that includes healthy fibre and probiotics may be a way to reduce inflammation and therefore the risk of cardiovascular disease.